Data storage devices may include decoders, such as error correction code (ECC) engines, that are used to correct errors in data that is stored at memories of the data storage devices. Some ECC engines use soft bits that indicates probabilities that one or more bits are correct (or incorrect) in order to decode a representation of data and to correct one or more errors. One type of information used to generate the soft bits is bit line defect information. Bit line defect information may indicate which bit lines of a memory are “bad bit lines.” Bad bit lines refer to bit lines that have defects (e.g., faults, flaws, and/or “errors”). At least some storage elements coupled to bad bit lines may have a high likelihood of storing incorrect data. A first type of bit line defect is referred to as a “closed defect” (e.g., a short). A closed defect occurs when one bit line is in contact with another bit line, causing all storage elements coupled to the two bit lines to have a high likelihood of storing incorrect data. A second type of bit line defect is referred to as an “open defect” (e.g., an “open”). An open defect occurs when there is a “break” in a bit line. Storage elements on one side of the break have a high likelihood of storing incorrect data, but storage elements on the other side of the break do not have an increased likelihood of storing incorrect data.
During fabrication and production of a data storage device, tests are performed to identify bad bit lines (e.g., bit lines having closed defects and open defects) at the memory. Bit line defect information for the entire memory is stored at the memory and is used to generate soft bits that are available to the ECC engine for use in decoding data. Because a bit line having an open defect is identified as a bad bit line, at least some storage elements (e.g., storage elements on one side of the break in the bit line) that do not have a high likelihood of storing incorrect data are incorrectly identified as having a high likelihood of storing incorrect data. Providing a decoder with soft bits that incorrectly identifies bits as having a high likelihood of being incorrect reduces an efficiency of the decoder, which increases processing time and power consumption of the decoder during the decoding process.